Successful Treatment of Recurrent Subcutaneous Cerebrospinal Fluid Retention : A Case Report

Abstract

We report a case of widespread and recurrent subcutaneous cerebrospinal fluid (CSF) retention in a 20-year -old female after a left frontotemporal craniotomy to remove a left frontal arteriovenous malformation (AVM). Examination found that a massive amount of cerebrospinal fluid was leaking into the subcutaneous space, distending it whenever she bowed her head; she also suffered from repeated headaches especially in the head-up position as a result of her low CSF pressure. The patient had manifested intracerebral hemorrhage clue to the frontal AVM at l0 years of age, and had undergone surgery to remove the hematoma. The total removal of the AVM had been performed 13 months prior to her present hospitalization. Her postoperative course had been uneventful, except for widespread subcutaneous CSF retention. Thus, a L-P shunt was inserted 2 months postoperatively, however, the subcutaneous CSF retention persisted unchanged. A S-P shunt that was added also did not change the patient's condition. On her second admission to hospital, a CT scan revealed an area of low density in the left frontal lobe that connected with the anterior horn of the left lateral ventricle. Thus, a frontotemporal craniotomy was performed through the previous operative wound. The brain surface was found to be covered by a thin neomembrane, and a small fistula was found sited between the subcutaneous space and the frontal horn of the left lateral ventricle. This fistula was found to be acting as a one-way valve for CSF from the ventricle to enter the subcutaneous space. Therefore by enlarging this fistula and adding a V-P shunt, the subcutaneous CSF retention disappeared.